Why getting different looking Pano results with GPU (versus CPU renderer) when spherical Override and Vertical FOVs are set the same values?

[JezUK]

I don't know why I am getting a different looking (and 'wrong') pano result when using the Spherical Default Override and the exactly the same settings in GPU as they were set for the CPU renderer ? (i.e. Override FOV set to 360 and Vertical FOV set to 90 for CPU).

a) why are the results different ?

b) what should I be setting the Vertical FOV ?

Okay, I worked out the the Vertical FOV for GPU Panoramas needs to be set to 180, but why isn't it the same value as is set when rendering using the CPU renderer ? (or is it because I now need to always choose Spherical Panorama whereas I'm comparing Spherical in CPU versus Spherical Panorama in GPU?)

PS - I'm using VRay Next.

[hermit.crab]

Yes, you should be comparing Spherical panorama (CPU) to Spherical panorama (GPU). The spherical camera has the Vertical and Horizontal FOV override parameters linked, whereas in the Spherical panorama they can be controlled independently.